test: production ingest E2E test suite with enhanced logging (#55)

## Summary
Production testing of ingest + embedding pipeline with api-gw integration.

## Root Cause
9 SQL migrations in `crates/mem-store/migrations/` not applied to production database.

Missing tables:
- `memory_entity`
- `memory_edge`
- `memory_edge_temporal`
- Vector embeddings tables
- And 15+ more schema objects

Evidence from logs:
```
WARN: Failed to save entity Docker:
      error returned from database: relation "memory_entity" does not exist
```

## Deliverables
- `test_prod_ingest_real.sh` - Full E2E test against K8s + api-gw
- `apply_migrations.sh` - Manual schema migration (backup)
- `collect_prod_logs.sh` - Pod log collection before/after
- `run_production_test.sh` - Test orchestrator
- `tests/integration_ingest_with_gw.rs` - Integration test
- `tests/unit_ingest_logging.rs` - Unit tests for extraction
- Enhanced logging in `ingest_worker.rs` - Per-record event tracking

## Next Steps
1. Trigger "DB Migration" workflow in Forgejo Actions
2. This applies all 9 migrations from `crates/mem-store/migrations/`
3. Pod restart (automatic)
4. Re-run E2E test - should pass completely

**ETA:** ~15 minutes (3-5 min migrations + 2 min restart + verification)

## How to Test Locally
```bash
./test_prod_ingest_real.sh --verbose
```

Requires:
- kubectl access to poimen namespace
- Port-forwarding to memory-service

---------

Co-authored-by: rock <[email protected]>
Reviewed-on: #55
Co-authored-by: poimen <[email protected]>

k8s/app/service-monitor.yaml

@@ -0,0 +1,15 @@
+apiVersion: monitoring.coreos.com/v1
+kind: ServiceMonitor
+metadata:
+  name: poimen-memory
+  namespace: poimen
+  labels:
+    app.kubernetes.io/name: poimen-memory
+spec:
+  selector:
+    matchLabels:
+      app.kubernetes.io/name: poimen-memory
+  endpoints:
+  - port: http
+    path: /metrics
+    interval: 30s